1. Field of the Invention
The present invention relates to a static convertor.
2. The Prior Art
In the event of a rectifier or valve failure in a static convertor, for example when a rectifier or valve does not ignite, the resultant disturbance may give rise to overvoltages and overtones of such a nature that all the rectifiers in a commutating group are blocked, which means that the DC side of the convertor is completely interrupted. The overvoltage thus produced involves a great risk that one or more rectifiers may be destroyed, particularly in large plants, for example power transmissions for high-voltage direct current.